High-pressure cleaning apparatus

ABSTRACT

In a high-pressure cleaning apparatus comprising a housing, a drive unit and a winding device for winding and unwinding leads which are led from stationary terminal connections to movable terminal connections, in order to enable safe and simple winding and unwinding of leads which lead away from the high-pressure cleaning apparatus, it is proposed that the winding device comprise a winding drum, that the winding drum comprise at least two separate winding areas, that an electric connecting cable for making a connection to a terminal connection which is stationary relative to the winding device be windable in the one winding area, that an electric connection cable for making a connection to a terminal connection which is movable relative to the winding device be windable in the other winding area, that an end of the connecting cable on the drum and an end of the connection cable on the drum form a direct connection point, that the connecting cable form a loop, that the winding area of the connecting cable be surrounded by a cable housing, in which also the loop has sufficient space in each wind position of the winding device, and that the other end of the connecting cable be led out of the cable housing through a stationary part of the cable housing and be fixed on the cable housing.

[0001] The present disclosure relates to the subject matter disclosed in international application PCT/EP99/05718 of Aug. 7, 1999, the entire specification of which is incorporated herein by reference.

[0002] The invention relates to a high-pressure cleaning apparatus comprising a housing, a drive unit and a winding device for winding and unwinding leads which lead from stationary terminal connections to movable terminal connections.

[0003] High-pressure cleaning apparatus usually comprise an electrically operated high-pressure pump, which, for operation purposes, has to be connected to a voltage supply unit. As a rule, electric cables, for example, extension cables which connect the high-pressure cleaning apparatus to an electric mains socket serve this purpose. In many cases, a winding device is provided for connection cables which are fixedly connected to the high-pressure cleaning apparatus, and the winding device comprises projections in the form of pins on the housing of the high-pressure cleaning apparatus, around which the connection cable can be wound and unwound. In high-pressure cleaning apparatus with such winding devices it is disadvantageous that the connection cable has to be wound and unwound again by hand in an awkward way, and that in the wound state, the connection cable lies unprotected on the outer housing.

[0004] Accordingly, the object of the present invention is to so design a high-pressure cleaning apparatus of the generic kind that leads which lead away from the high-pressure cleaning apparatus can be easily and safely wound and unwound.

[0005] In accordance with the invention, this object is accomplished in that the winding device comprises a winding drum, that the winding drum comprises at least two separate winding areas, that an electric connecting cable for making a connection to a terminal connection which is stationary relative to the winding device is windable in the one winding area, that an electric connection cable for making a connection to a terminal connection which is movable relative to the winding device is windable in the other winding area, that an end of the connecting cable on the drum and an end of the connection cable on the drum form a direct connection point, that the connecting cable forms a loop, that the winding area of the connecting cable is surrounded by a cable housing in which also the loop has sufficient space in any wind position of the winding device, and that the other end of the connecting cable is led out of the cable housing through a stationary part of the cable housing and is fixed on the cable housing.

[0006] This design enables simple winding of the connection cable onto and unwinding of the connection cable from the winding drum, namely by the winding drum being rotated. The connection cable is wound in the angular range provided therefor. Furthermore, this design has the advantage that all slip ring contacts are dispensed with. As a rule, these are provided when leads leading from stationary terminal connections to movable terminal connections are wound onto winding drums so as to prevent twisting of the leads. The twisting of the leads can also be prevented without slip ring contacts because instead of a slip ring contact, a connecting cable fixedly connected on the drum to the connection cable and fixedly arranged at its other end on the high-pressure cleaning apparatus forms a loop.

[0007] Such winding devices for winding and unwinding leads leading from stationary terminal connections to movable terminal connections, for example, on a crane, are known per se, for example, from DE 29 00 187 A1. During the winding and unwinding of the connection cable, the loop of the connecting cable is simultaneously wound onto and off a separate winding area of the winding drum. The connecting cable does not become twisted, and, therefore, slip ring contacts can be dispensed with.

[0008] A further advantage of the present invention is the arrangement of the connecting cable in a housing. The housing serves to protect the connecting cable against any outer influences, for example, dirt and contact with fluids. In this way, it is possible to arrange all electric connection points in the housing of the high-pressure cleaning apparatus. The cable housing also serves to spatially delimit the connecting cable during the winding and unwinding, whereby safe and orderly winding and unwinding of the connecting cable is simultaneously made possible.

[0009] In a preferred embodiment of the invention provision is made for the cable housing to so delimit the winding area of the connecting cable in a radial direction that the loop when unwound to a maximum extent abuts on the radial delimitation of the winding area. When the connection cable is being unwound, the connecting cable is simultaneously unwound with it. If the maximum extent of the cable housing in a radial direction is limited, the connecting cable unwinds from the winding drum and simultaneously winds onto the inner circumferential wall of the cable housing surrounding the winding area. In the present case, a minimum size of the cable housing is thereby fixed. In this way, the winding device takes up a minimum space.

[0010] In principle, provision may be made for the winding drum to have an essentially radially symmetrical cross section. The cables can be wound in a particularly simple and neat way onto winding drums with a radially symmetrical, for example, round cross section.

[0011] It is advantageous for the cable housing to have an essentially radially symmetrical cross section. Since the connecting cable is wound onto the inner circumferential wall of the cable housing as the connecting cable unwinds from the winding drum, a neat winding and unwinding are ensured when the cross section of the cable housing is radially symmetrical, for example, circular.

[0012] Provision is made in accordance with a preferred embodiment for the winding drum to be surrounded essentially radially symmetrically by the cable housing. In this way, a spacing between the winding drum and the inner circumferential wall of the cable housing is fixed, whereby the connecting cable can be wound and unwound in a particularly neat and trouble-free way.

[0013] It is expedient for the drum diameter of the winding area of the connection cable to be greater than the drum diameter of the winding area which accommodates the connecting cable. The structural size of the winding device can be additionally minimized by a small drum diameter of the winding area of the connecting cable.

[0014] It is particularly advantageous for the cable housing to be protected against spray water. During operation of the high-pressure cleaning apparatus, it is virtually unavoidable for the apparatus to come into contact with spray water. In view of this, electric components must be water-tight from the start, or at least accommodated in a housing so as to be protected against spray water. In the present invention there is an additional connection point, namely between the connection cable and the connecting cable. For this reason, a cable housing for the connecting cable, which is protected against spray water, is desirable for operational reliability.

[0015] In a preferred embodiment of the present invention provision is made for the connecting cable to be wound in an initial position in the same direction as the connection cable completely on the winding drum, in a middle position to be completely unwound, whereby a maximum loop is formed, and upon further movement of the winding drum to be wound on again completely in the reverse winding direction with the loop being drawn in. This results in the special advantage that the connecting cable is shorter than the connection cable. This reduces the costs for the connection cables and the structural size of the winding device. The size of the loop is additionally reduced by the shortening of the connecting cable, whereby the winding and unwinding of the connecting cable can be carried out in a way which is even less susceptible to disturbance.

[0016] It is expedient for the connecting cable to be approximately half as long as the connection cable. When the length of the connecting cable is half that of the connection cable, both the connecting cable and the cable housing are absolutely minimized.

[0017] It is advantageous for the drum cross section of the winding area of the connecting cable to have a heart-shaped indentation, and for one end of the connecting cable to be led via the indentation to the connection point with the connection cable. Owing to the heart-shaped indentation, the connecting cable can be led from the circumference of the drum of the winding area into the center of the drum without snapping at any point. The heart-shaped indentation offers the further advantage that with a reduced cable length of the connecting cable, the connecting cable can be wound in both winding directions in a kink-free way.

[0018] In principle, provision may be made for the connecting cable to be formed by a flat ribbon cable. Flat ribbon cables can be wound onto winding drums in a particularly neat and uniform way, and, in addition, they minimize the radial extent of a wound-up cable by way of their elongate cross section.

[0019] It is expedient for the connection cable to be formed by a round cable. The connection cable can be drawn out of the winding device to a voltage supply unit, and it is expedient for it to be bendable equally well in all directions. This is the case with a round cable.

[0020] In a particularly preferred embodiment of the invention, provision may be made for the winding drum to be able to be held in the initial position relative to the housing by a clamping device. The clamping device makes it possible for the connection cable to wind up again independently in the winding device when the pull on the connection cable relaxes. This is particularly convenient and always ensures that the connection cable is wound off with the minimum required length.

[0021] It is expedient for the clamping device to be formed by a spiral spring, one end of which is fixed on the winding drum and the other on the housing. A spiral spring adapts particularly well to the structural shape of the winding drum.

[0022] Furthermore, provision may be made for a reverse lock to be provided on the winding drum. The reverse lock prevents the connection cable from winding up again unintentionally. In this way, the connection cable once it is unwound, remains unwound to the desired length.

[0023] In principle, provision may be made for one end of the connecting cable to be connected to the drive unit. The connecting cable constitutes the extension of the connection cable, and, therefore, both cables serve as connection between the drive unit and the voltage supply unit.

[0024] It is particularly advantageous for the cable housing to be part of the housing. In this way, a separate cable housing can be dispensed with when it is directly integrated into the housing of the high-pressure cleaning apparatus. This minimizes the material requirements as well as the structural size of the winding device.

[0025] The following description of a preferred embodiment of the invention serves in conjunction with the drawings the purpose of further explanation. The drawings show:

[0026]FIG. 1 a longitudinal section through a winding device integrated into a high-pressure cleaning apparatus;

[0027]FIG. 2 a cross-sectional view along line 2-2 from FIG. 1 through the cable housing of the connecting cable in the wound-up state of the connection cable;

[0028]FIG. 3 a cross-sectional view similar to FIG. 2, but with the connecting cable completely unwound;

[0029]FIG. 4 a cross-sectional view similar to FIG. 2, but with the connection cable completely unwound and the connecting cable wound in the opposite direction.

[0030] A cable drum 1 of a high-pressure cleaning apparatus, not shown in greater detail, is to be seen in FIG. 1. An inner drum delimiting wall 2 arranged transversely to the axis of rotation DA of the cable drum 1 comprises a cylinder-shaped projection, which serves as drum bearing 3, and the axis of symmetry of which defines the axis of rotation DA. On its side facing away from the drum delimiting wall 2, the drum bearing 3 is surrounded in a positively fitting manner by a cup-shaped drum hub 4 which is rotatable about the axis of rotation DA relative to the drum bearing 3. In the plane of the inner drum delimiting wall 2 there extends from the drum hub 4 in a radial direction a circular-disk-shaped projection which forms a hub disk 5. The inner drum delimiting wall 2 is offset in the area of the radial extent of the hub disk 5 in the direction of the axis of rotation away from the hub disk 5 in the direction opposite to the cup-shaped opening of the drum hub 4 and thereby forms a ring-shaped recess.

[0031] On the side of the hub disk 5 facing away from the recess there is arranged on the hub disk 5 a circular-disk-shaped drum inner disk 6, whose outer diameter is approximately twice the diameter of the drum hub 4 and which is connected by a radial sleeve-like circumferential wall 7 to the hub disk 5. The circumferential wall 7 extends in the direction of the axis of rotation away from the hub disk 5 beyond the drum inner disk 6 by a distance which is approximately 1.5 times further than the distance hub disk 5/drum inner disk 6. On the side of the circumferential wall 7 facing away from the hub disk 5, the circumferential wall 7 comprises a radial circular-disk-shaped projection which forms a delimiting disk 8 which extends parallel to the outer area of the inner drum delimiting wall 2 and the hub disk 5. The delimiting disk 8 extends in a radial direction from the drum hub 4 as far as the inner drum delimiting wall 2.

[0032] Parallel to the delimiting disk 8 and to the inner drum delimiting wall 2 there extends a partition wall 9 which on its inner circumference facing the drum hub adjoins the circumferential wall 7 seamlessly and almost over the entire area between drum inner disk 6 and delimiting disk 8. Drum inner disk 6 and partition wall 9 extend in the same plane.

[0033] In its radial outer area, the partition wall 9 comprises a sleeve-like projection extending in the direction of the axis of rotation towards the inner drum delimiting wall 2 over the entire circumference and engaging under a similar projection of the inner drum delimiting wall 2 projecting in the opposite direction. These two projections form a radial wall 10 of a winding space 11 of a flat ribbon cable 12, which is additionally delimited by the hub disk 5, the outer area of the inner drum delimiting wall 2, the partition wall 9 and the circumferential wall 7. The flat ribbon cable 12 is wound in layers onto the essentially circular cross section of the circumferential wall 7.

[0034] Furthermore, a drum outer disk 14 is arranged on the side of the delimiting disk 8 facing away from the winding space 11 via a sleeve-shaped ring 13 acting as spacer. The drum outer disk 14 extends parallel to the delimiting disk 8. A winding area 16 is defined by the drum outer disk 14, the ring 13, the delimiting disk 8 and a projection of a shape similar to that of the radial wall protruding in the direction opposite to the latter and forming a housing edge 15. A stub 17 arranged eccentrically on the hub disk 5 serves to receive a likewise cylindrical connecting piece 18 which protrudes from the delimiting disk 8 in the direction of the hub disk 5 and expands in the form of a single step on its side facing the drum outer disk 14 and serves to receive a pin 19 which is joined to the drum outer disk 14 on its side facing the delimiting disk 8. The axes of symmetry of stub 17, connecting piece 18 and pin 19 extend parallel to the axis of rotation. The last-mentioned parts can be adhered to one another or secured to one another by a screw, not shown in greater detail.

[0035] A rotatably mounted supply roll 20 for a spiral spring 21 is arranged on the inner drum delimiting wall 2 on its side facing away from the winding space 11. One end of the spiral spring is connected to the supply roll 20, the other end to the hub disk 5. When rotated out of an initial position, the hub disk 5 is thereby turned back into the initial position by the spring force of the spiral spring 21 in a manner known to an expert in the field of cable drums.

[0036] The cable drum 1 comprises a winding space 11 and a winding area 16, whose radial inner delimitations are fixed relative to each other and upon rotation of the hub disk 5 or the drum hub 4 are rotated in the same direction about the drum bearing 3. The winding space 11 serves to receive the flat ribbon cable 12, the winding area 16 to receive a round cable 22. The inside end of the flat ribbon cable 12 is guided inwards via a heart-shaped indentation 23 in the circumferential wall 7, which otherwise has an essentially round cross section. Similarly, the inside end of the round cable 22 is guided inwards at an opening, not illustrated, in the ring 13 in the direction of the axis of rotation. These two ends of the flat ribbon cable and the round cable 22 are electrically conductively connected to each other, insulated and fixed on the rotating parts of the cable drum 1 in a manner not shown herein in further detail. The other end of the flat ribbon cable 12 is guided at a point on the radial wall 10 through a passage 24 out of the winding space 11. The passage 24 simultaneously serves to fix the flat ribbon cable on the radial wall 10.

[0037] A reverse lock generally designated by reference numeral 25, which is arranged between the partition wall 9 and the delimiting disk 8 rotatable relative thereto, prevents the cable drum 1 from returning to the initial position against the spring force exerted by the spiral spring 21 in a manner known to the expert in the field of cable drums.

[0038] The procedure of unwinding and winding the connection cable of the high-pressure cleaning apparatus in the form of a round cable 22 is to be seen in FIGS. 2 to 4. In an initial position shown in FIG. 2, the free end of the connection cable protrudes out of the housing of the cable drum 1. The flat ribbon cable 12 is completely wound on the circumferential wall 7 of the winding space 11. In the initial state, it is also possible for the outermost winding layer of the flat ribbon cable 12 not to be wound closely on the layers thereunder but for it to loosely surround these wound layers lying thereunder. If the operator of the high-pressure cleaning apparatus pulls the connection cable out of the cable drum 1, the flat ribbon cable 12 simultaneously unwinds. A more or less loose loop 26 is formed. The unwound loop 26 is outwardly delimited by the radial wall 10. The loop 26 reaches its maximum size when the flat ribbon cable 12 is completely unwound from the circumferential wall 7. This position referred to as middle unwound position of the cable drum is shown in FIG. 3. If the connection cable is unwound further, the movable parts of the cable drum 1 rotate further as a whole in the clockwise direction. However, upon further rotation, the flat ribbon cable is then wound onto the circumferential wall 7 in the counterclockwise direction. In an end position, the connection cable is completely unwound, and the flat ribbon cable 12 is wound on the circumferential wall 7 again completely, but in the counterclockwise direction.

[0039] Each wind position of the cable drum 1 can be fixed by the reverse lock 25. The spiral spring described hereinabove serves for easier winding of the connection cable. The winding procedure takes place in the reverse order to the unwinding procedure described above.

[0040] The parts of the cable drum 1 surrounding the winding space 11 are arranged relative to one another and sealed off from one another in such a way that the winding space 11 is protected from spray water.

[0041] The cable drum 1 can be integrated as a whole in the housing of a high-pressure cleaning apparatus. On the other hand, it is possible for the inner drum delimiting wall 2 to be part of the housing of the high-pressure cleaning apparatus, and parts of the high-pressure cleaning apparatus can thereby also form parts of the cable drum 1 at the same time. 

What is claimed is:
 1. High-pressure cleaning apparatus comprising a housing, a drive unit and a winding device (1) for winding and unwinding leads, which are led from stationary terminal connections to movable terminal connections, characterized in that the winding device (1) comprises a winding drum (4, 5, 7, 13), in that the winding drum (4, 5, 7, 13) comprises at least two separate winding areas (11, 16), which are only wide enough for single-layer cables to be windable therein lying one above the other in layers, in that an electric connecting cable (12) for making a connection to a terminal connection which is stationary relative to the winding device (1) is windable in the one winding area (11), in that an electric connection cable (22) for making a connection to a terminal connection which is movable relative to the winding device (1) is windable in the other winding area (16), in that an end of the connecting cable (12) on the drum and an end of the connection cable (22) on the drum form a direct connection point, in that the connecting cable (12) forms a loop (26), in that the winding area (11) of the connecting cable (12) is surrounded by a cable housing (2, 7, 9, 10), in which also the loop (26) has sufficient space in each wind position of the winding device (1), and in that the other end of the connecting cable (12) is led out of the cable housing (2, 7, 9, 10) through a stationary part (24) of the cable housing (2, 7, 9, 10) and is fixed on the cable housing (2, 7, 9, 10).
 2. High-pressure cleaning apparatus as defined in claim 1 , characterized in that the cable housing (2, 7, 9, 10) delimits the winding area (11) of the connecting cable (12) in a radial direction such that the loop (26) when unwound to a maximum extent abuts on the radial delimitation (10) of the winding area (11).
 3. High-pressure cleaning apparatus as defined in claim 1 , characterized in that the winding drum (4, 5, 7, 13) has an essentially radially symmetrical cross section.
 4. High-pressure cleaning apparatus as defined in claim 1 , characterized in that the cable housing (2, 7, 9, 10) has an essentially radially symmetrical cross section.
 5. High-pressure cleaning apparatus as defined in claim 1 , characterized in that the winding drum (4, 5, 7, 13) is surrounded essentially radially symmetrically by the cable housing (2, 7, 9, 10).
 6. High-pressure cleaning apparatus as defined in claim 1 , characterized in that the drum diameter of the winding area (16) of the connection cable (22) is greater than the drum diameter of the winding area (11) which accommodates the connecting cable (12).
 7. High-pressure cleaning apparatus as defined in claim 2 , characterized in that the drum diameter of the winding area (16) of the connection cable (22) is greater than the drum diameter of the winding area (11) which accommodates the connecting cable (12).
 8. High-pressure cleaning apparatus as defined in claim 1 , characterized in that the cable housing (2, 7, 9, 10) is protected against spray water.
 9. High-pressure cleaning apparatus as defined in claim 2 , characterized in that the cable housing (2, 7, 9, 10) is protected against spray water.
 10. High-pressure cleaning apparatus as defined in claim 1 , characterized in that in an initial position, the connecting cable (12) is wound in the same direction as the connection cable (22) completely on the winding drum (4, 5, 7, 13), in a middle position is completely unwound, whereby a maximum loop (26) is formed, and upon further movement of the winding drum (4, 5, 7, 13) is wound on again completely in the reverse winding direction with the loop (26) being drawn in.
 11. High-pressure cleaning apparatus as defined in claim 2 , characterized in that in an initial position, the connecting cable (12) is wound in the same direction as the connection cable (22) completely on the winding drum (4, 5, 7, 13), in a middle position is completely unwound, whereby a maximum loop (26) is formed, and upon further movement of the winding drum (4, 5, 7, 13) is wound on again completely in the reverse winding direction with the loop (26) being drawn in.
 12. High-pressure cleaning apparatus as defined in claim 1 , characterized in that the connecting cable (12) is approximately half the length of the connection cable (22).
 13. High-pressure cleaning apparatus as defined in claim 2 , characterized in that the connecting cable (12) is approximately half the length of the connection cable (22).
 14. High-pressure cleaning apparatus as defined in claim 10 , characterized in that the connecting cable (12) is approximately half the length of the connection cable (22).
 15. High-pressure cleaning apparatus as defined in claim 1 , characterized in that the drum cross section of the winding area (11) of the connecting cable (12) has a heart-shaped indentation (23), and in that one end of the connecting cable (12) is led via the indentation (23) to the connection point with the connection cable (22).
 16. High-pressure cleaning apparatus as defined in claim 1 , characterized in that the connecting cable (12) is formed by a flat ribbon cable.
 17. High-pressure cleaning apparatus as defined in claim 1 , characterized in that the connection cable (22) is formed by a round cable.
 18. High-pressure cleaning apparatus as defined in claim 16 , characterized in that the connection cable (22) is formed by a round cable.
 19. High-pressure cleaning apparatus as defined in claim 1 , characterized in that the winding drum (4, 5, 7, 13) is adapted to be held in the initial position relative to the housing (2) by a clamping device (20, 21).
 20. High-pressure cleaning apparatus as defined in claim 19 , characterized in that the clamping device is formed by a spiral spring (21), one end of which is fixed on the winding drum (4, 5, 7, 13) and the other on the housing (2).
 21. High-pressure cleaning apparatus as defined in claim 1 , characterized in that a reverse lock (25) is provided on the winding drum (4, 5, 7, 13).
 22. High-pressure cleaning apparatus as defined in claim 1 , characterized in that one end of the connecting cable (12) is connected to the drive unit.
 23. High-pressure cleaning apparatus as defined in claim 1 , characterized in that the cable housing (2, 7, 9, 10) is part of the housing. 